Asterisk

Asterisk is an open-source voice-over-IP (VOIP) platform. With Asterisk, administrators can turn any computer into a communications server such as IP PBX systems, VOIP gateways and conference servers. Sponsored by Digium, the software appliance is available as AsteriskNOW and there are a number of vendors that sell Asterisk-based appliances.

Ask any Linux aficionado, the platform's primary strength lies in its flexibility and versatility. While the most obvious example is how Google built the Android mobile operating system on top of the Linux kernel, there are many customized operating systems that are dedicated to specific types of hardware or platforms that have Linux at their core. Some distributions are also specifically designed to target certain types of users or to solve a very specific task. While the well-known ones, such as Canonical's Ubuntu, Red Hat Enterprise Linux, SUSE and Mandriva are great server and desktop distributions and can probably handle most conceivable system administration tasks, some people just prefer having an operating system that does one thing and does it well. There are Linux flavors dedicated to multimedia editing, network monitoring, security testing, and basic system administration functions. Many of these are based on Debian or Ubuntu, but others have been built from scratch. For this slide show, eWEEK has found some interesting specialized Linux distributions that can make the IT administrators' day a little bit easier.